The present invention relates to a valve arrangement. In particular, the invention relates to a valve arrangement suitable for fluid connectors or connection modules for use in connecting instrumentation equipment to a fluid container such as a process line or pressure vessel.
Within the instrumentation industry, it is necessary to take fluid from a fluid container such as a process pipeline or pressure vessel, so as to take measurements of quantities such as pressure, temperature, flow and fluid level measurements.
The instruments which are used to take such measurements are typically connected to a fluid container by a system of pipes, manifolds and valves. The connection system can include one or more tapping connections for tapping the fluid container.
The instruments which are used to take such measurements require maintenance, such as calibration. In order to carry this out it is necessary to modify the flow of the fluid between the fluid container and the instrument.
This flow modification is currently carried out by a number of methods all of which in some way require systems which are attached to the main process apparatus by means of threaded, flanged or welded connections. Traditionally the fluid passes through an isolation valve before being passed through tubing, pipe work or flanges to other valves commonly held within a manifold block. This manifold block may either be attached directly to the instrument or attached via a further system of tubing or pipe work.
There is a trend to legislate to regulate emissions of potentially harmful substances to the environment, for example the EU's IPPC directive 96/61/EC aimed at minimizing pollution from various industrial sources throughout the European Union. An important part of this legislation is reducing fugitive emissions, which will have significant consequences for all processes. According to the IPPS all plants and factories which fail to comply with the standards set by the directive may be closed from this point.
A typical European refinery looses between 600 and 10,000 tons of emissions per annum. Around 70% of these losses are estimated to be caused by plant equipment such as pipe flanges, pumps, valves and vessels. Leakage from valves is often the biggest source, reportedly accounting for around 50% of the fugitive emissions within the chemical and petrochemical industries.
Irrespective of the environmental impact, there is a tremendous financial burden on industry because fugitive emissions represent a huge loss of product, and cause of plant inefficiency. However, the true costs to industry are not always appreciated, as many of the costs associated with fugitive emissions are hidden, such as labor and materials to repair leaks, wasted energy, environmental fines and clean up costs, lost sales due to a poor green image, claims for personal injury and more. In this way, reducing fugitive emissions not only protects the environment, but can save companies time and money.